OCPP protocols and their use in SmartCharging

Advice and explanations

OCPP connects a charging station to its management system. Supporting a protocol version alone does not confirm support for every function. When connecting a station, we verify the particular model, firmware and required scenarios. Connecting SmartSystem to building control is designed separately, for example through Modbus RTU or TCP.

OCPP is an open protocol for communication between a charging station and its management system. The following comparison explains the communication principle, rather than listing the functions available on every AgeVolt device.

OCPP 1.6 vs. OCPP 2.0.1

OCPP 1.6 is one of the most widely used protocol versions, providing a broad range of charging management functions. It is stable, widely supported and sufficiently flexible for most applications.

  • Advantages:
    • Stability and broad support
    • Availability of many implementations and solutions
    • Extensibility through extended messages
  • Disadvantages:
    • Fewer functions compared with newer versions
    • Less advanced dynamic control capabilities

OCPP 2.0.1 is a newer protocol version that introduces several improvements and new functions. It is intended for advanced applications requiring greater flexibility and more control options.

  • Advantages:
    • Advanced dynamic control functions
    • Improved support for security and authentication
    • Extended charging station management and monitoring capabilities
  • Disadvantages:
    • Less support and fewer available implementations compared with OCPP 1.6
    • Greater implementation complexity and effort

Extended messages and data transfer

Extended messages can add data to communication between a station and its management system. The specific data and commands depend on the implementation. SmartSystem obtains data from the building or solar installation through appropriate metering and a separately configured connection.

Connecting metering and the building
  1. Monitoring building consumption:
    • SmartSystem can obtain the required data from SmartMeters or a compatible building system through Modbus RTU or TCP, depending on the particular installation.
  2. Integration with solar power:
    • control can use measured surplus generation. The data source and communication method are selected according to the metering and connected devices.
  3. Security functions:
    • OCPP 2.0.1 provides advanced authentication and data encryption options. Extended messages can be used to improve communication security between charging stations and the central system.

Practical use of OCPP in AgeVolt EMS

The design must distinguish connecting stations to the platform from obtaining building data. The following situations are illustrative examples, rather than descriptions of specific verified installations.

  1. Public car parks:
    • Compatible stations in a car park can be connected to a shared management system. Control distributes the available power according to configured limits and charging data.
  2. Office buildings:
    • a compatible building system can pass the available power or measured data to the controller through Modbus. The particular interface and mapping are configured during integration.
  3. Homes with solar power:
    • suitable metering supplies data on consumption and surplus power. Control adjusts charging according to this data within the capabilities of the station and vehicle.

Conclusion

OCPP can simplify connecting a compatible station to a shared management system. Available control and reporting functions are verified for the particular implementation, rather than merely relying on the protocol version label.

The next article explores practical advice for designers, including cable design and charging station installation with AgeVolt EMS.

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